Based in Boston, where she teaches at the Berklee College of Music and Boston Conservatory, Marti Epstein is a composer who writes music of ethereal slowness that somehow never loses a sense of solidity and groundedness. An immersion in her works is likely to induce a renewed awe for the wonder of sound itself, suspended in space and, seemingly, in time as well.

Trinity Wall Street music director Julian Wachner, who credits Epstein with introducing him to the music of Anton Webern, hit on the imaginative idea of pairing the two composers’ music in the current iteration of the “Time’s Arrow” concert series, the first part of which was presented last September. Listeners can hear the collocation on June 19 and 21, in person at St. Paul’s Chapel or via livestream on the Trinity Wall Street website. (Streamed shows are archived for playback just hours later.)

In a recent interview, Epstein spoke to National Sawdust Log about composing, Webern, and what it’s like for her to hear her creations come to life.

NATIONAL SAWDUST LOG: I read somewhere that you didn’t decide to become a composer so much as you decided that that’s what you were.

MARTI EPSTEIN: Yes, that’s true.

What does that mean?

Well, it means that for my whole life, when I was a kid, I played the piano and other instruments. I always gravitated to music and always wanted to be a musician. It never occurred to me to compose until my high school band director [in Omaha, NE] said, “if you’re going to be a musician, there are an awful lot of great pianists in the world. You might want to do something a little bit different. And since you’re good at music theory, maybe you should try composing.” I can’t explain why I never thought about that before – I just hadn’t.

He had me write some flute obbligato for a band. And I wrote it. and the band played it. And I immediately knew that that’s what I was doing with my life. I know that sounds weird, like how could it really be true? But it was true. And then started taking lessons at the University of Nebraska. It seemed like the thing I should have been doing all along.

You didn’t have a lot of exposure to contemporary music when you were growing up.

That’s correct.

So as you got a better sense for what composers had been doing in the 20th century, what effect did that have on your own musical language?

Well, that was the most important part of the story. I knew I was a composer and that was what I was going to study in college. But the only living composer I could name was John Williams. (As an aside, when we have students audition at Boston Conservatory and we ask them if they know any living composers, they still say “John Williams.”) So I went to the University of Iowa, and [Bang on a Can co-founder] David Lang was my ear-training teacher. He said, “if you want to be a composer, you have to know what’s going on.” And he came up with this listening list that included Steve Reich and Philip Glass and John Cage and Morton Feldman and all these people. They all had a profound influence on me – it was like a drug, almost.

Morton Feldman’s music was the music that completely changed my life. Sometimes I’m hesitant to tell people that, because then people say, “Oh yeah, I totally hear the Feldman influence.” And I think there’s way too much going on in my music to be truly Feldmanesque. Josh Gordon, cellist in the Lydian String Quartet, calls my music “Feldman without the misogyny,” which I think is sad and hilarious all at once. And then Takemitsu is a huge early influence. And Webern.

It was huge, because it really broke down all of the ideas I had of what my music could and should sound like. I realized that music could be completely unimaginable, something I hadn’t even imagined before.

Tell me about your connection to Julian Wachner.

I don’t remember this, but Julian does, and he tells this story – it’s like an implanted memory. I used to give talks to the high school students at the Boston University Tanglewood Institute. Julian was in one of the classes, where I was talking about my connection to Webern and how beautiful I think Webern’s music is. That was Julian’s watershed moment. Mine was David Lang telling me about Feldman, and his was me telling him about Webern.

Then Julian came to school at Boston University and he and I got to know each other. And he became music director at Marsh Chapel and commissioned a piece from me. The rest is sort of history.

Of the canonical 20th-century composers – we could debate who’s in that canon and who isn’t – I think Webern is the most divisive. What is it that you find so enthralling about his music?

I’ll preface what I’m about to say by first agreeing with you. But also, I think that Webern is also the founding father of all the strands of modern music. The strict serialists looked to him, but also Feldman and Cage looked to him.

For me it’s not about the serialism, it’s about the pointillism, if I’m going to put an -ism on it. Melodic and accompanimental textures are not what’s important in his music; what’s important in his music are the actual sound structures themselves, the individual note itself being an available sound to create a piece around. It’s about the sparseness of it, the poetry of it. It’s about the spaces between things, which is the thing Cage and Feldman were attracted to in his music. So that’s what it is for me.

On one of the concerts they’re doing two string quartets of mine and Webern’s Five Pieces for String Quartet. And that was the piece of Webern’s that was the most influential for me. I always go back to that piece.

Tell me more about the works that are on the Trinity concerts.

On June 19 is my very long string quartet that I wrote in 2012 for the Tanglewood Festival of Contemporary Music, Hidden Flowers. It’s about 24 minutes long at the correct tempos. There’s also a very short, four-minute piece I wrote for the Lydian String Quartet called Phosphenes. Phosphenes are the lights you see when you rub your eyes. It was written specifically to be a complement to Hidden Flowers, so I’m glad they’re doing them together.

Then on June 21 they’re doing Oil and Sugar, which is a piece for violin, flute, clarinet, and piano. That piece was inspired by a video of the same name, which lived at the ICA Boston. It’s sugar cubes with motor oil poured on them, and it’s really beautiful how the sugar kind of crumples in. There are all these little sparkles. Also on that program is a solo harp piece called Wonders of the Invisible World that I wrote for Hannah Lash. She’s played that piece probably a dozen times.

[Note: A piece for harp and percussion planned for the series was canceled because of difficulties of procuring certain instruments.]

It’s sort of an unusual order, a solo harp piece. How did you approach it?

It was a little bit intimidating, writing a piece for a composer who plays the harp. She had one really important requirement, which is that she wanted me to respond to her Harp Sonata. She’s not so into extended techniques – she wasn’t interested in me putting honey spoons on the strings and then hitting them with a mallet, things I wasn’t very excited about either. So I responded to her piece, which is very virtuosic harp music. And I decided to do something which is sort of the inverse of that. So my piece is very sparse, it has just a few materials in it, but they’re very thought out and constructed. It’s as if her piece were put behind a curtain and you can barely hear some of the things in it – that’s what my piece is.

In earlier concerts in this series, you heard your works alongside Webern’s music (as well as those of other composers). I’m wondering how that juxtaposition felt.

You know, it’s funny. Some people think my music is very avant-garde. Some people think it’s very conventional. It just depends on your outlook. Compared to Webern, it almost seemed like, I don’t know, Puccini or someone. It just seemed really Romantic, in a way I never imagined thinking about it. I could also hear the connection, a direct connection, but I don’t know if that was obvious to the people who were there. It was great, actually.

So, what are you working on right now?

Well, I just started writing a 10-minute opera for Boston Opera Collaborative. They do these little “Opera Bites” things – I just started working on mine. I’m a little bit scared because I didn’t chose the libretto; I was given a bunch, and I chose from that. None of them really spoke to me, and this was the one I liked the most. I often find the most interesting things that happen artistically is when you put two things together that you never would have imagined go together. This libretto, I don’t know if I would have chosen it on my own. Also, the “Opera Bites” pieces are generally fairly conservative, and I’m not going to write a conservative piece; I’m going to write a piece that’s me, whatever that is.

I feel like I’m being pushed out of my comfort zone. I feel like I’m always lecturing to my students that they need to not be in a comfort zone; they need to get out of the comfort zone. So now I’m essentially walking the walk and talking the talk at the same time. And it’s scary, but I feel like every composer has to do that.

And after that?

After that, I’m working on a piano concerto for one of our students in the contemporary classical performance program at Boston Conservatory. He’s an amazing pianist, and he asked me to write a concerto. And it’s one of these things where this isn’t a paid commission, and I’d move heaven and earth to write this piece. That will be my labor of love at the end of the summer.

I get the sense from talking to composers that actually hearing the sound of a piece in the air is always different than seeing it on paper or screen. So I wonder if the experience of hearing your own piece at a concert is always… surprising in some way.

That’s actually not a simple question. First of all, I never use a computer – there’s no MIDI playback or anything like that. I try as hard as I can to hear the music in my head and write down what that is. That’s what I try to get my students to do. And I feel like composers who don’t do that, you can always tell.

The second thing is, the more of your music you hear, the less of a surprise it is. If you’re taking risks and being imaginative, there’s always going to be a gap between what’s in your head and what you hear. And that gap is not a bad thing – it’s what makes you take risks. But the more you do it, the more you can close the gap a little bit. I feel like the older I get, the more music of mine I hear, the narrower that gap gets, and the surprises are less.

But there’s a variable, which is the performance itself. I had an amazing experience at a Trinity Wall Street concert in September. I heard a piece of mine that I have heard played many times. It’s a clarinet, viola, and piano piece [See, Even Night]. I’ve always thought it was one of my better pieces. But it was a performance that was head and shoulders beyond any other. I was truly astonished when I heard it – I thought, oh my God, I had no idea this piece could sound this amazing. I had this experience hearing the Lydian String Quartet several weeks ago.

So the variable of the performers playing your music is really huge, and if you’re not happy with a piece, as a composer, you have to be willing to untangle what’s you and what’s the performance.

Music by Marti Epstein is performed by Novus NY musicians in “Time’s Arrow” concerts at St. Paul’s Chapel (209 Broadway) on June 19 and 21 at 1pm; trinitywallstreet.org.